# Ap physics at my highschool gave me a hard question

1. Dec 2, 2007

### chyle

A baseball has a mass of about 0.14 kg, and it is pitched towards home plate at a speed of about 46 m/s. If the bat exerts an average force of 8900 N for 2.1 ms, what is the final speed of the ball in m/s?

2. Dec 5, 2007

### Shooting Star

Do you know what is the impulse of a force? Impulse = change in momentum. Using that, this is definitely a very easy problem. Of course, we have to assume that the ball went back right the way it came.

3. Dec 11, 2007

### Petkovsky

Impuls and change of momentum

F *$$\Delta$$t = m * $$\Delta$$v

$$\Delta$$v is the change in velocity that you have, not the velocity by itself, but you probably know that :)